Scooby-Doo! and the Samurai Sword

In ancient Japan, Masamune begins crafting the Sword of Fate, a mighty blade that will take a year to complete. Muramasa proposes a faster rival blade, the Sword of Doom, which carries evil power. The warrior who would bear the Doom is corrupted by its magic, becoming the Black Samurai. After Masamune finishes the Sword of Fate, the Green Dragon battles the Black Samurai and imprisons him inside the Doom. He then hides the Doom and marks its whereabouts with a Destiny Scroll riddle for future seekers.

Muramasa completes the Sword of Doom in half the time, and its corrupting magic taints the wielder. The resulting Black Samurai embodies the weapon's malevolence. The Sword of Fate remains separate, awaiting its destined bearer.

Masamune finishes the Sword of Fate. The Green Dragon battles the Black Samurai and imprisons him inside the Sword of Doom. The whereabouts of the Doom sword are hidden on the Destiny Scroll via a riddle for future seekers.

In present-day Tokyo, Mr. Takagawa and Kenji witness the Black Samurai seemingly come to life during an exhibit at the Museum of Ancient History. The unnerving sight signals that a long-dormant threat may be waking. The incident foreshadows the adventure to come.

The Mystery Inc. gang travels to Mirimoto Academy near Tokyo for a martial arts tournament, where Daphne is invited to participate. They meet Miyumi, Miss Mirimoto, Sojo, and Takagawa.

Takagawa warns Mirimoto of the Black Samurai's plan to steal the Destiny Scroll. The Black Samurai leads an army of ninjas to attack the academy and seems to steal the scroll, but Mirimoto reveals she stole a copy and provides the real scroll to Mystery Inc.

Shaggy and Scooby unknowingly solve the Destiny Scroll riddle, prompting Mirimoto to send the gang to locate the Sword of Doom before the Black Samurai. The quest sets them on a perilous journey toward the uncharted island.

The gang reaches an uncharted island in the Pacific Ocean and confronts island natives and the Black Samurai's forces. The battles test their resolve as they advance toward the Sword of Doom.

Amid the island battles, the Mystery Inc. crew unmasks the Black Samurai as Sojo and retrieves the Sword of Doom, returning to Mirimoto with the blade.

Back at Mirimoto's scheme, Miyumi betrays the team to support Mirimoto, who reveals a plan to resurrect the Black Samurai and program the robotic ninjas by exploiting the tournament.

Daphne passes the Sword of Doom to Shaggy and Scooby, and they escape on a jetpack. They are pursued by robot ninjas, who eventually steal the Sword of Doom during the chase.

Kenji unknowingly frees Mystery Inc. and Takagawa, who build an EMP device to disable the robots.

Miyumi repents and tries to seize the Sword of Doom, but Mirimoto retrieves it so Sojo can free the Black Samurai from it. The Black Samurai proclaims he serves no one, defeats Mirimoto and Sojo, and subdues the others.

Shaggy, Scooby, and the Green Dragon, aided by Matsuhiro, confront the Black Samurai. Scooby uses the Sword of Fate to destroy the Sword of Doom, breaking the curse and rendering the samurai mortal. He thanks Mystery Inc. before dying.

Mystery Inc. attends the newly renovated museum, where a statue of Scooby is erected to honor his role in saving Japan. They invite Miyumi to join them on their travels, but she declines to focus on herself.